Add version depndent intersphinx mapping (#3960)

* Add version depndent intersphinx mapping

* Sort import

* Granular intersphinx mapping

* Ruff formatting

* Use importlib to get python version of program

* Oneliner

* Fix versioning test

* Fix basix reference

* Update intersphinx mapping for documentation versions

* Fix syntax for dictionary entries in conf.py

* Ruff fix.

* Tidy.

* Fix numpy version string.

---------

Co-authored-by: Jack S. Hale <mail@jackhale.co.uk>

Author: jorgensd

python/doc/source/conf.py

@@ -6,7 +6,15 @@
 import os
 import sys
 
+import mpi4py
+
+import numpy as np
+import packaging
+
+import basix
 import dolfinx
+import ffcx
+import ufl
 
 sys.path.insert(0, os.path.abspath("."))
 import jupytext_process  # isort:skip
@@ -152,14 +160,50 @@
 
 codeautolink_concat_default = True
 
+# Could be reimplemented using packaging.version
+dolfinx_version = "main" if "dev0" in dolfinx.__version__ else "v" + dolfinx.__version__
+basix_version = "main" if "dev0" in basix.__version__ else "v" + basix.__version__
+ffcx_version = "main" if "dev0" in ffcx.__version__ else "v" + ffcx.__version__
+ufl_version = "main" if "dev0" in ufl.__version__ else ufl.__version__
+
+numpy_version = packaging.version.parse(np.__version__)
+numpy_doc_version = f"{numpy_version.major}.{numpy_version.minor}"
+
+# Note that as of late 2025 pyvista and petsc4py only have docs for the latest
+# releases.
 intersphinx_mapping = {
-    "basix": ("https://docs.fenicsproject.org/basix/main/python/", None),
-    "ffcx": ("https://docs.fenicsproject.org/ffcx/main/", None),
-    "ufl": ("https://docs.fenicsproject.org/ufl/main/", None),
-    "mpi4py": ("https://mpi4py.readthedocs.io/en/stable", None),
-    "petsc4py": ("https://petsc.org/release/petsc4py", None),
-    "numpy": ("https://numpy.org/doc/stable/", None),
-    "pyvista": ("https://docs.pyvista.org/", None),
+    "petsc4py": (
+        "https://petsc.org/release/petsc4py",
+        None,
+    ),
+    "numpy": (
+        f"https://numpy.org/doc/{numpy_doc_version}",
+        None,
+    ),
+    "pyvista": (
+        "https://docs.pyvista.org",
+        None,
+    ),
+    "mpi4py": (
+        f"https://mpi4py.readthedocs.io/en/{mpi4py.__version__}",
+        None,
+    ),
+    "dolfinx": (
+        f"https://docs.fenicsproject.org/dolfinx/{dolfinx_version}/python",
+        None,
+    ),
+    "basix": (
+        f"https://docs.fenicsproject.org/basix/{basix_version}/python",
+        None,
+    ),
+    "ffcx": (
+        f"https://docs.fenicsproject.org/ffcx/{ffcx_version}",
+        None,
+    ),
+    "ufl": (
+        f"https://docs.fenicsproject.org/ufl/{ufl_version}",
+        None,
+    ),
 }
 
 napoleon_google_docstring = True

python/dolfinx/__init__.py

@@ -44,7 +44,10 @@
     has_slepc,
     ufcx_signature,
 )
-from dolfinx.cpp import __version__
+
+from importlib.metadata import metadata
+
+__version__ = metadata("fenics-dolfinx")["Version"]
 
 _cpp.common.init_logging(sys.argv)
 del _cpp, sys

python/test/unit/common/test_version.py

@@ -1,20 +1,18 @@
-# Copyright (C) 2021 Chris Richardson
+# Copyright (C) 2021-2025 Chris Richardson, Jørgen S. Dokken
 #
 # This file is part of DOLFINx (https://www.fenicsproject.org)
 #
 # SPDX-License-Identifier:    LGPL-3.0-or-later
 
-from importlib.metadata import version
 
 import dolfinx
 
 
 def test_version():
     """Test that installed Python version matches C++ version."""
-    py_version = version("fenics-dolfinx")
     # Change any final '.dev0' to '.0'
-    py_version = py_version.replace("dev", "")
-    cpp_version = dolfinx.__version__
+    py_version = dolfinx.__version__.replace("dev0", "0")
+    cpp_version = dolfinx.cpp.__version__
     if py_version != cpp_version:
         raise RuntimeError(
             f"Incorrect versions. Python version: {py_version}, Core version: {cpp_version}"